Answer:
 
 
Explanation:
 we know that 
The simple interest formula is equal to 
 
 
where 
A is the Final Investment Value 
P is the Principal amount of money to be invested 
r is the rate of interest 
t is Number of Time Periods 
in this problem we have 
 
 
substitute in the formula above and solve for t
 
 
![t=[(645/600)-1]/0.025=3\ years](https://img.qammunity.org/2020/formulas/mathematics/high-school/v73l14av5aj6kp2oj1pj2j3snvgc6j87wl.png)